I had a buddy who did it for a couple of years. He was a really top notch statistician and programmer, who received a whopping inheritance and decided to leave his 9-5 and become a day trader.

He made ok-ish money for two years. Then he lost the lot. 

Short-term stock trading is gambling, and its more rigged than most casinos - https://web.archive.org/web/20230328054737/https://www.2iqresearch.com/blog/profiting-from-insider-transactions-a-review-of-the-academic-research

Insider trading in our "capitalist" societies is a major way in which the privileged and useless maintain their status and wealth, without hard work or discernable talents.

If you socialise with those people and get the hot tips, day trading can make you rich.